using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;

namespace Luzes
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;

        Vector3 cameraPosition;
        Vector3 lookAt;
        Vector3 vetor;

        KeyboardState teclado;

        Model modelo;

        Texture2D textura;

        BasicEffect basicEffect;

        public enum TiposEfeitoBasico
        {
            Nenhum,
            LuzesAmbiente,
            UmaLuz,
            TresLuzes
        }

        TiposEfeitoBasico tipoAtual = TiposEfeitoBasico.TresLuzes;


        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
            vetor = new Vector3(-1, 1, 0);
        }

        /// <summary>
        /// Allows the game to perform any initialization it needs to before starting to run.
        /// This is where it can query for any required services and load any non-graphic
        /// related content.  Calling base.Initialize will enumerate through any components
        /// and initialize them as well.
        /// </summary>
        protected override void Initialize()
        {
            // TODO: Add your initialization logic here

            base.Initialize();
        }

        /// <summary>
        /// LoadContent will be called once per game and is the place to load
        /// all of your content.
        /// </summary>
        protected override void LoadContent()
        {
            // Create a new SpriteBatch, which can be used to draw textures.
            spriteBatch = new SpriteBatch(GraphicsDevice);

            basicEffect = new BasicEffect(GraphicsDevice);

            cameraPosition = new Vector3(0, 5, 5);
            lookAt = Vector3.Zero;

            basicEffect.Projection = Matrix.CreatePerspectiveFieldOfView(
                MathHelper.PiOver4,//abertura
                GraphicsDevice.Viewport.AspectRatio,//taxa de proporcao da tela
                1.0f,//plano de "perto"
                10000.0f);//plano de "longe"

            basicEffect.View = Matrix.CreateLookAt(
                cameraPosition,
                lookAt,
                Vector3.Up);

            modelo = Content.Load<Model>("caixa");

            switch (tipoAtual)
            {
                case TiposEfeitoBasico.LuzesAmbiente:
                    basicEffect.EnableDefaultLighting();
                    break;
                case TiposEfeitoBasico.UmaLuz:
                    basicEffect.LightingEnabled = true;
                    basicEffect.DirectionalLight0.Enabled = true;
                    basicEffect.DirectionalLight0.DiffuseColor = Color.Green.ToVector3();
                    basicEffect.DirectionalLight0.Direction = Vector3.Normalize(new Vector3(-1, -1, 0));
                    break;
                case TiposEfeitoBasico.TresLuzes:
                    basicEffect.LightingEnabled = true;
                    basicEffect.DirectionalLight0.Enabled = true;
                    basicEffect.DirectionalLight0.DiffuseColor = Color.Green.ToVector3();
                    basicEffect.DirectionalLight0.Direction = Vector3.Normalize(new Vector3(0, -1, 0));
                    basicEffect.DirectionalLight1.Enabled = true;
                    basicEffect.DirectionalLight1.DiffuseColor = Color.Red.ToVector3();
                    basicEffect.DirectionalLight1.Direction = Vector3.Normalize(new Vector3(1, 1, 0));
                    basicEffect.DirectionalLight2.Enabled = true;
                    basicEffect.DirectionalLight2.DiffuseColor = Color.Blue.ToVector3();
                    basicEffect.DirectionalLight2.Direction = Vector3.Normalize(vetor);
                    break;

            }

            // TODO: use this.Content to load your game content here
        }
         
        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            // TODO: Unload any non ContentManager content here
        }

        /// <summary>
        /// Allows the game to run logic such as updating the world,
        /// checking for collisions, gathering input, and playing audio.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Update(GameTime gameTime)
        {
            // Allows the game to exit
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();

            teclado = Keyboard.GetState();

            if (teclado.IsKeyDown(Keys.A))
            {
                basicEffect.DirectionalLight2.Direction += new Vector3(0.1f, 0, 0);
            }

            else if (teclado.IsKeyDown(Keys.D))
            {
                basicEffect.DirectionalLight2.Direction -= new Vector3(0.1f, 0, 0);
            }
            
            else if (teclado.IsKeyDown(Keys.W))
            {
                basicEffect.DirectionalLight2.Direction += new Vector3(0.1f, 0.1f, 0);
            }

            else if (teclado.IsKeyDown(Keys.S))
            {
                basicEffect.DirectionalLight2.Direction -= new Vector3(0.1f, 0.1f, 0);
            }

                // TODO: Add your update logic here

            base.Update(gameTime);
        }

        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.CornflowerBlue);

            switch (tipoAtual)
            {
                case TiposEfeitoBasico.LuzesAmbiente:
                case TiposEfeitoBasico.UmaLuz:
                case TiposEfeitoBasico.TresLuzes:
                    DrawModel(modelo, Matrix.Identity*Matrix.CreateRotationY(MathHelper.ToRadians(45)), basicEffect);
                    break;
            }

            // TODO: Add your drawing code here

            base.Draw(gameTime);
        }

        private void DrawModel(Model m, Matrix world, BasicEffect be)
        {
            foreach (ModelMesh mm in m.Meshes)
            {
                foreach (ModelMeshPart mmp in mm.MeshParts)
                {
                    be.World = world;
                    GraphicsDevice.SetVertexBuffer(mmp.VertexBuffer, mmp.VertexOffset);
                    GraphicsDevice.Indices = mmp.IndexBuffer;
                    be.CurrentTechnique.Passes[0].Apply();
                    GraphicsDevice.DrawIndexedPrimitives(PrimitiveType.TriangleList, 0, 0, mmp.NumVertices, mmp.StartIndex, mmp.PrimitiveCount);
                }
            }
        }
    }
}
